Narayana IIT Academy INDIA Sec: Sr. IIT_IZ JEE-MAIN Date: Time: 07:30 AM to 10:30 AM Cumulative Test Max.Marks: 360

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1 INDIA Sec: Sr. IIT_IZ JEE-MAIN Date: Tme: 07:30 AM to 10:30 AM Cumulatve Test Max.Marks: 360 KEY SHEET PHYSICS MATHS CHEMISTRY

2 SOLUTIONS PHYSICS 1. 4 If we gve the followng nputs to A and B, then correspondng output s shown n table A B C The above table s smlar to OR gate.. the reverse basng results n very hgh resstance across the p-n juncton. If the value of the resstance R s ncreased, the current n the forward based nput crcut decreases. The emtter current I E decreases and hence the collector current C E B I I I also decreases. The glowness of the bulb decreases. Due to decrease n I C, the potental drop across the bulb B decreases and hence the voltmeter sows a lower voltage. 3. Optcal source frequency f 8 c Hz Number of channels or subscrbers E VLED 8 0mA R R Sec: Sr.IIT_IZ Page

3 6V R 300 0mA Also reverse voltage across red dode s V whch s fne for LED wth reverse breakdown voltage of 3V let E c be the ampltude of carrer wave and Es s sgnal ampltude then E C V max V mn max mn, E V V s EC mec 4 m6 m 3 7. J E t kx c 0 sn d dt E 0 0 de A dt 0 AE0 cost kx Jd J c J E Some of the characterstcs of an optcal fbre are as follows () ths works on the prncple of total nternal reflecton. () It conssts of core made up of glass/slca/plastc wth refractve ndex n 1, whch s surrounded by a glass or plastc claddng (graded ndex fbre). () There s a very lttle transmsson loss through optcal fbres. Sec: Sr.IIT_IZ Page 3

4 (v) There s no nterference from stray electrc and magnetc feld to the sgnal through optcal fbres. 14. For permanent magnet we prefer a materal wth hgh retentvty (so as to make a stronger magnet) and hgh coercvty (so that magnetzaton any not be wped out easly). For electromagnet we prefer hgh saturated magnetsm low coercvty and least possble area of hysteress loop so that electromagnet develops hgh magnetzaton, s easly demagnetzed and energy loss n a magnetzaton cycle s least. Therefore, P s sutable for makn permanent magnet and for makng electromagnet h h mv Km y A B. B Let ntal ntensty of lght s I 0. So ntensty of lght after transmsson from frst I 0 Polarod Sec: Sr.IIT_IZ Page 4

5 Raylegh crteron: When the central maxmum of one source falls on the frst mnmum of another source, the sources are sad to be just resolved.. Out-put s XOR GATE A & B two are nput 3. XOR output A. B. B A 5. dampng coeffcent km m m Sec: Sr.IIT_IZ Page 5

6 ma b A b B m 1 m mb 6. on ncreasng temperature of semconductor bond between molecule break so more electron become free to move hence. Conductng ncreases and moblty decreases. 7. f 1.6MHz fmodulatng 750 khz 8. 3 E C 10 A V V R R 1.5V 5V 30. Mnmum magnfyng power mage s at D m f For mcroscope dmn sn dmn D D sn 1. For eye, mn d 1. d Dsn mmn d Dsn 3. MATHS 33. x 48, n=00 standard devaton = 3 Sec: Sr.IIT_IZ Page 6

7 Varance x x 4600 x x n n 35. ~ p q ~ p q q p p q q p ~ ~ p q ~ ~ q p And p p q p ~ p q s not a tautology. 36. x x x x var. 7 4 var S. D use ~ p q p q Opton () s correct. x x 38. use: 0 0 n n n 5 n n 39. npq 1 1 p q, n P x 1 C C mean of mean of y k k () Standard devaton of (standard devaton of y ) 15.1 () 1.5 and k 5 Sec: Sr.IIT_IZ Page 7

8 41. use: contrapostve of p q s ~ q ~ p 4. do yourself m P, x 1 x 1 4 P m n1 10, n 10 Average m1 60, m 40 4, 6 1 Standard devaton of combned seres 1 1 n n n n m m n n n n Sec: Sr.IIT_IZ Page 8

9 Let x 1, x... x n be n observatons, then 1 X x x Let y 10, then 49. n X 10 Y y x 10n Y X 10 n 1 n n 50. mean = Varance d y n 1 y C. V % x x n Hence answer (3) s correct Sec: Sr.IIT_IZ Page 9

10 54. we know that p q p q p q ~ ~ p q ~ p q p ~ q Hence (3) s correct opton 55. contrapostve of a b s ~ b ~ a Hence (D) s correct opton 56. use the property ~ a b a ~ b Hence (3) s correct opton 57. use the property ~ p q p ~ q Hence () s correct opton CHEMISTRY 63. Sol:- Lanthanod elements havng same number of unpared electrons have same colours xf and 14 x f confguratons have same number of unpared electrons. 64. Sol:- Due to lanthande contracton covalent character of lanthande compounds ncreases from La to Lu. So basc character of ther oxdes and hydroxdes deceases from La OH 3 to Lu OH Sol:- Europum has 4b 6s confguraton. So t exhbts oxdaton state due to the stablty of half-flled oxdaton state 3 of lanthanods 7 4 f confguraton n Eu.. Also t exhbts the common Sec: Sr.IIT_IZ Page 10

11 66. Sol:- Due to lanthanode contracton the atomc szes of 4d and 5d seres elements n a group have same atomc szes and hence ther propertes are also nearly valency Sol:- In La 4 f no possblty of f there s no possblty of f f 7 transton also n 4 4 f f. There s f transton due to spn forbdden rule. So they are colourless Sol:- Ce by loosng four electrons gets the 4 f o confguraton. 70. Refer NCERT Pg no:- 8 XII part-i 7. Sol:- Aspartame s made fron aspartcacd and phenyl alanne 80. Refer NCERT Pg no:-19 ass-xii part Paraldehyde, chloral hydrate [C3CHC(OH)] possess sedatve and hypnotc propertes as they act an CNS. 8. Dettol s a mxtrue of chloroxylenol and Terpneol. 83. Most contraceptve plls contan norethndrone, ethynyl estradol and mfeprstone etc. 84. Analgn (or) novalgn s used as analgesc & antpyretc. 86. Asprn s a non-norcotc drug 88. NHCOCH 3 OH (Paracetamol) 89. (or) C6H66 1,, 3, 4, 5, 6 - hexa chlorocyclohexane. NHCOCH 90. Chloramphencol O N CH CH CH OH OH Sec: Sr.IIT_IZ Page 11